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What to check in the factory test before you pay the balance

We ask buyers to pay the balance only after they have seen the factory test evidence. Here is what to look for.

Diesel generator sets

• Nameplates: engine and alternator serial numbers and models match the quotation.
• Load test: on a resistive load bank at 25%, 50%, 75%, 100% and 110% (prime) for the agreed time; record voltage, frequency, current, oil pressure and coolant temperature at each step.
• Voltage and frequency stability: steady-state and recovery after load steps within the ISO 8528 class stated.
• Protections: low oil pressure, high temperature, overspeed and emergency stop actually shut the set down.
• Controller: auto start, readings on the display match the load bank meters.
• Canopy or container: doors, fuel tank, no leaks after the run.

Distribution transformers (routine tests, IEC 60076)

• Winding resistance.
• Voltage ratio and vector group check.
• Short-circuit impedance and load loss.
• No-load loss and current.
• Applied and induced voltage withstand tests.
• Insulation resistance; oil tests where specified.

How you can witness

• Live video call during the test, showing the meters (we offer this on orders of US$ 150,000 and above; smaller orders get the recorded test video).
• Signed test report with photos and serial numbers.
• Third-party inspection by BV, SGS or Intertek; a one-day witness inspection in Jiangsu or Shandong costs roughly US$ 600 and needs 3–5 working days' notice.